Centrifugal pump.



ILED DEC. 6 1905 w in 3|: WIFQ w H m mm .N J x N \x MP III a: x

erases.

TES PATENT Enron.

CENTRIF'UGAL PUMP.

To all whom it may concern:

Be it known that I, FERDINAND W. KRoeH, a citizen of the United States,residing in the city and county of San Francisco and State ofCalifornia, have invented certain new and useful Improvements inCentrifugal Pumps, of which the following is a specification.

The object of my invention is to relieve the impelling wheel of acentrifugal pump from friction by making it float in the liquid passingthrough the pump.

In carryin out my invention I provide the pump cas ng with a.cylindrical chamber opposite the suction opening, and I provide theimpelling wheel with a piston or plunger, located centrally, like a hub,which plays in this chamber; I also provide two passages connecting thischamber respectively with the suction and discharge of the pump, throughwhich liquid is withdrawn from, or supplied to the chamber. Thesepassages open into the chamber in such way that their openings arecontrolled by the plunger, one being open when the other is closed.

In the accompanying drawings I have shown a horizontal pump containingmy invention in its best form.

The figure shows the pump in sectional elevation.

In the figure :1 is the casing of the pump, and 2 the impeller wheelrotating therein, and mounted on the shaft 8.

4 is the suction opening of the casing, and 5 is the discharge.

6-is a cylindrical well or chamber, opposite the suction opening a. Thischamber or well has inlet and outlet ports 6" and 6, herein designatedas pressure and suction ports, respectively, as they are connected withmeans through which the chamber or well is supplied with liquid underpressure and with means for suctionally withdrawing said liquid.

7 is the piston or plunger on the wheel, fitting and playing in thechamber and adapted to close the ports 6 and 6 alternately bypredetermined variations in the position of the impeller wheel from itscondition of balance. It is preferably hollow, as shown, and openinteriorly to the chamber or well.

8 is a pipe connecting the chamber with the suction 4 of the pump, and 9is a similar pipe cmmecting the chamber with the dis- Specification ofLetters Patent.

Application filed December 6, 1905.

Patented Get. 4, 1910.

Serial No. 290,619.-

charge 5 of the pump. These pipes are controlled respectively by valves10 and 11.

12 is a groove in the outer surface of plunger 7, in such a positionthat it comes opposite the mouth of pipe 9 when the wheel is in itslower position in the casing, as indicated by the dotted line, at whichtime the mouth of pipe 8 is covered and closed by the plunger. Thegroove 12 communicates with the interior of the chamber by means ofholes 18 pierced at intervals, as shown.

In operation, if the wheel is at the'upper part of its casing, in theposition shown, the pipe 9 is closed, or nearly so, by the plunger, andthe pipe 8 is open. Hence liquid is withdrawn from chamber 6 by thenatural suction of the pump operating through the suction opening 4, andthe wheel is drawn downward. But if the wheel is in its lower position,indicated by the dotted line in the lower part of the chamber the pipe 8is closed by the plunger, and the pipe 9 communicates with the chamberthrough the groove 12, and liquid is forced into the chamber from thepump discharge through the pipe 9, and the impeller wheel 2 is pushedupward. These two effects alternate until, at some intermediate point,an equilibrium is established, and the wheel floats in the liquidpassing through the pump.

Particular attention is called to the fact that I have provided a mostsimple and effective means for the purpose in view. Thus the pressurechamber 6 is arranged at the side of the casing opposite the suctionportion of the pump, or in other words, at the side of the impellerremote from the pumpsuction, and the plunger 7 is at the closed side ofthe impeller and is formed partly by an element of said closed side, andpartly by a ported wall which moves with the impeller and in saidchamber, and controls the pressure admitted into the space encircled bysaid wall, through the ports from the pressure and suction portions ofthe pump.

I claim 1. A self balancing centrifugal pump comprising a casing havinga suction inlet and a pressure outlet, a ported pressure chamber, pipesrespectively connecting the ports of the chamber with the inlet andoutlet, and an impeller wheel arranged within the easing directly abovethe chamber and provided with a depending hollow plunger adapted in oneposition to close the port of the chamher connecting the inlet saidplunger being 1 provided with a passage which is adapted, in anotherposition of the plunger, to communicate directly between the other portof the chamber and the interior of the plunger.

2. A self balancing centrifugal pump comprising a casing having asuction chamber, pipes respectively connecting the ports of the chamber,with the inlet and outlet, and an impeller wheel arranged within thecasing directly above the chamber and provided with a depending hollowplunger adapted, in one position, to close the port of the chamberconnecting the inlet, said plunger being provided with an exteriorcircumferential groove and spaced ports, which are adapted, in anotherposition of the plunger. to communicate directly between the other portof the chamber and the interior of the plunger.

In testimony whereof I have afiixed my signature in presence ofsubscribing witnesses this 20th day of November 1905.

FERDINAND W. KROGH.

Witnesses TM. S. BATES, A. S. FARE.

